Semiconductor devices are used in a large number of electronic devices, such as computers, cell phones, and others. Semiconductor devices comprise integrated circuits that are formed on semiconductor wafers by depositing many types of thin films of material over the semiconductor wafers, and patterning the thin films of material to form the integrated circuits. Integrated circuits include field-effect transistors (FETs) such as metal oxide semiconductor (MOS) transistors.
One of the goals of the semiconductor industry is to continue shrinking the size and increasing the speed of individual FETs. To achieve these goals, fin FETs (FinFETs) or multiple gate transistors will be used in advanced transistor nodes. For example, FinFETs not only improve areal density but also improve gate control of the channel.
In an effort to increase the performance and reduce the power consumption of complementary metal-oxide-semiconductor (CMOS) and MOSFET devices, the semiconductor industry has employed high mobility semiconductors to replace silicon as the transistor channel. The semiconductor industry has also encouraged substrate isolation techniques through, for example, silicon on insulator (SOI) and heterostructure devices, which can improve off-state characteristics.
Corresponding numerals and symbols in the different figures generally refer to corresponding parts unless otherwise indicated. The figures are drawn to clearly illustrate the relevant aspects of the embodiments and are not necessarily drawn to scale.